Palladium catalyzed tandem alkenyl- and aryl-C-N bond formation: a cascade N-annulation route to 4-, 5-, 6- and 7-chloroindoles

A series of trihalogenated alkenylbenzenes undergo consecutive palladium catalyzed inter- and intramolecular amination reactions to deliver a series of 1-functionalized mono-chloroindoles. 4-, 5-, 6- and 7-Chloroindoles can all be prepared; carbamates, anilines and amines can be employed as the N-nucleophile.